The flip side is, what's the point of a freemium model if the free product gives most users what they want, so they have no incentive to ever pay to upgrade?

The flip side is, what's the point of a freemium model if the free product gives most users what they want, so they have no incentive to ever pay to upgrade? I've been a dropbox user for years and haven't paid them a penny since the free product does everything I need it to.